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D3 and React - the future of charting components? - Binary Consulting. Data-Driven Documents (D3.js) is currently my favoured charting library for producing interactive SVG visualisations. Typically, I chose to use it in combination with NVD3. It provides a higher level library of re-usable charts and chart components for D3.

Another JavaScript library that has taken my interest recently is React by Facebook. It aims to be just the View, or V in MVC, for building rich web application user interfaces. Why React? Two reasons that I find it of interest are firstly due to the implementation of a virtual DOM allowing very efficient and high performance browser DOM manipulation. This also allows a React JavaScript application to be entirely rendered on the server when using Node.js for the initial page load or SEO benefits. The example taken from React's homepage illustrates this point, with the <HelloMessage /> component being appended to a DOM node.

The JSX compiler converts the XML syntax to vanilla JavaScript function calls. Chart Bar Data Series Stacked bar chart. Sarah Mei » Why You Should Never Use MongoDB. Disclaimer: I do not build database engines. I build web applications. I run 4-6 different projects every year, so I build a lot of web applications. I see apps with different requirements and different data storage needs. I’ve deployed most of the data stores you’ve heard about, and a few that you probably haven’t. I’ve picked the wrong one a few times. The project Diaspora is a distributed social network with a long history. But they hit a nerve. Diaspora was the first Kickstarter project to vastly overrun its goal. As a result of their Kickstarter success, the guys left school and came out to San Francisco to start writing code. They ended up staying at Pivotal for more than two years. That’s a lot of buzzwords. “Distributed social network” If you’ve seen the Social Network, you know everything you need to know about Facebook.

A screenshot of the Diaspora user interface The Diaspora infrastructure is not located behind a single web address. 1. 2. 3. 4. Comments work the same way. Ok. Cut Two Pieces: Inkscape. Do you use Inkscape? Did you know there is a built in feature to create calendars? If you don’t have Inkscape but would like to make a calendar go here and download the program (it is free). To create a calendar is very easy.

To start open Extensions>Render>Calendar. Now you will see a new window with some more options. Make any changes and press Apply when finished to create your calendar. To make further changes ungroup several times. If you wish to share the calendar you create you may prefer to save it as a PDF document so friends who do not own Inkscape can also print the calendar. Edited - 29-10-2012 A reader has asked how to change the year of the calendar. Gephi - The Open Graph Viz Platform. How Selections Work. Any sufficiently advanced technology is indistinguishable from magic. –Arthur C. Clarke In the past I have presented simplified descriptions of D3’s selections, providing only enough detail to get started. This article takes a more comprehensive approach; rather than saying how to use selections, I will explain how selections are implemented. This may take longer to read, but it should dispel any magic and help you master data-driven documents. The structure of this article may at first seem arbitrary. It describes the internal workings of selections rather than the design motivations, so you may wonder why such mechanisms are needed. D3 is a visualization library, so this article incorporates visual explanations to accompany the text.

Var array = [42]; Wherever possible, the code that generates the given selection appears immediately above the diagram. Let’s begin. #A Subclass of Array You were probably told that selections are arrays of DOM elements. #Grouping Elements d3.selectAll("h2"); Hierarchy for D3.js :: ObjJob.


Tutorials. Getting Started with D3: Safari Books Online. Learning D3 Part 1: Selections, Properties, Data | Synthesis | Scott Becker. Update: I’m releasing a series of screencast tutorials on D3 at Check it out and let me know what you think! I thought I’d take a stab at learning D3, the JavaScript data visualization library. To start, I picked through some of the examples and tried the code running in my own browser. Once I played around with some of the code and saw a sine wave drawn on the screen, modified some values and saw the change, I thought “awesome!”.

D3 is not a high level library where you can feed it some data, and simply get back charts and graphs. So, D3 is built around some core principles. Selections Selections are essentially the same as jQuery selectors, and defined by the W3C selectors API. jQuery – select all paragraphs: D3 – select all paragraphs: In this way, D3 is declarative. Dynamic Properties Styles, attributes, and other properties of the DOM can be specified as functions of data in D3, as opposed to simple constants.

Set the color style of all paragraphs to a simple value: Bound Data. LondonJS: 11 Things You Didn't Know About D3' LondonJS, 21/10/13 I'm a freelance web developer Anna Powell-Smith 11 THINGS I DIDN"T KNOW ABOUT d3... ...until I sat down and read the entire API docs Photo by river2sea on Flickr JavaScript library for data visualisation One JavaScript file, 145KB minified, BSD licensed Launched late 2010, now the 6th most-starred library on GitHub Used in production by New York Times, GitHub, Square...

Source: Mike Bostock (click to start) 2005: Prefuse (Java, Heer, Berkeley) 2007: Flare (ActionScript, Heer, Berkeley) 2009: Protovis (JavaScript, Heer/Bostock, Stanford) 2011: D3 (JavaScript, Heer/Bostock, Stanford) TLDR: very smart people thought very hardabout visualisation for a very long time BEFORE d3 var data = google.visualization.arrayToDataTable([ ['Year', 'Sales', 'Expenses'], ['2004', 1000, 400], ['2005', 1170, 460] ... ]); var chart = new google.visualization.BarChart (document.getElementById('chart_div')); chart.draw(data, options); Expenses var dataset = [ 5, 10, 13, 19, 21, 25, WITH D3: Transitions. D3.js Playground. Sorting a selection in d3.js disturbs the data-join. API Reference · mbostock/d3 Wiki.


Chained Transitions. Selections. Arrays. Interactive Data Visualization for the Web. Contrary to what the name implies, D3 layouts do not, in fact, lay anything out for you on the screen. The layout methods have no direct visual output. Rather, D3 layouts take data that you provide and remap or otherwise transform it, thereby generating new data that is more convenient for a specific visual task.

It’s still up to you to take that new data and generate visuals from it. Here is a complete list of all D3 layouts: Bundle Chord Cluster Force Histogram Pack Partition Pie Stack Tree Treemap In this chapter, I introduce three of the most common: pie, stack, and force. If you are curious about any of the other D3 layouts, check out the many examples on the D3 website, and be sure to reference the official API documentation on layouts. d3.layout.pie() might not be as delicious as it sounds, but it’s still worthy of your attention.

Figure 11-1. Feel free to open up the sample code for this in 01_pie.html and poke around. Remember radians? Var pie = d3.layout.pie(); D3.


Stacked Bar. Animations and transitions. That post originally appeared on, I’m reproducing it here for clarity and ease of retrieval In interactive visualisation, there is the word reactive. Well, maybe not literally, but close enough. The fact is that reactivity, or the propension of a visualisation to respond to user actions, can really help engage the user in a visualisation, and help them understand its results. Both of which are usually good things. And how can this reactivity be achieved?

So I’ll go ahead and state that animation, if done right, can make any interactive data visualization better.. When coupled with interaction, it’s a very useful way to give feedback to the user. That’s said, animation can definitely ruin your visualization, too. Animation is very prominent. Now how to do it? So we’ve seen how animation is helpful in data visualization. The principle If you know how to draw in d3, you almost know how to animate. And what do we mean by characteristics? A few examples of transitions How this is done. Path Tween. Smooth Slider. D3, Conceptually - Lesson 0: Preface. If you don't know what D3 is, the short answer is "a Javascript library people use to make cool charts".

The long answer is, as expected, much longer. This tutorial hopes to bridge some of that distance. It is a work-in-progress. D3 is a powerful tool, but you know how that saying goes: "With great power comes a conceptually clean library with a learning curve like a wall". Or something like that. Because D3 is really a beautiful little library, enlightening in how it solves the problem of turning data into documents. This tutorial assumes you know about HTML and CSS, as well as some JS. You won't need any tools, though to play along at home I'd recommend getting the library, setting up a skeleton page that includes it, and becoming comfortable with the JS console in your browser of choice. d3: scales, and color. In protovis, scales were super-useful in just about everything. That much hasn’t changed in d3, even though d3.scale is a bit different from pv.Scale.

(do note that d3.scale is in lowercase for starters). Scales: the main idea Simply put: scales transform a number in a certain interval (called the domain) into a number in another interval (called the range). For instance, let’s suppose you know your data is always over 20 and always below 80. You would like to plot it, say, in a bar chart, which can be only 120 pixels tall. You could, obviously, do the math: But what if you suddenly have more or less space? This is much simpler, elegant, and easy to maintain. . … only more legible and shorter. Fun with scales In d3, quantitative scales can be of several types: linear scales (including quantize and quantile scales,logarithmic scales,power scales (including square root scales) While they behave differently, they have a lot in common. Domain and range Clamping Scales and nice numbers .nice() .ticks(n) El Patrón de los Números Primos: Prime Number Patterns.

By Jason Davies. For each natural number n, we draw a periodic curve starting from the origin, intersecting the x-axis at n and its multiples. The prime numbers are those that have been intersected by only two curves: the prime number itself and one. Below the currently highlighted number, we also show its sum of divisors σ(n), and its aliquot sum s(n) = σ(n) - n, which indicate whether the number is prime, deficient, perfect or abundant. Based on Sobre el patrón de los números primos by Omar E. Pol. Brush Handles. Orthographic Shading. Lab and HCL Color Spaces. D3 supports CIELAB (Lab) and CIELCH (HCL) color spaces, which are designed for humans rather than computers. Lab and HCL color spaces are special in that the perceived difference between two colors is proportional to their Euclidean distance in color space.

This special property, called perceptual uniformity, makes them ideal for accurate visual encoding of data. In contrast, the more familiar RGB and HSL color spaces distort data when used for visualization. You can create Lab or HCL colors in D3 directly using d3.lab or d3.hcl. For example: var steelblue = d3.lab(52, -4, -32); var steelblue = d3.hcl(-97, 32, 52); You can also convert from other color spaces, such as RGB or HSL.

Var lightsteelblue = d3.lab("#4682b4").brighter(); var darksteelblue = d3.hcl("hsl(207, 44%, 49%)").darker(); Most importantly, you can use d3.interpolateLab or d3.interpolateHcl in conjunction with quantitative scales and transitions: For more on this topic: Vis.